Quote:
Originally Posted by 4corners
I found this on Edmonds.com
The 328i SULEV uses the N51 versus the N52 engine. In order to comply with SULEV requirements, the N51 is a variant of the N52 engine. Some of the SULEV measures for the N51 include:
• Near engine catalyst with additional underbody catalyst
• Secondary air system
• Optimized combustion chamber geometry in cylinder head
• Modified piston crown for lower compression
• Plastic valve cover with integrated crankcase vent valve and separator (from N52KP)
• Stainless steel fuel lines with threaded connections
• Radiator with “Prem-air” coating
• Throttle system - EGAS08 carried over from N52KP
• Airbox with Activated carbon filter for EVAP control
• Purge system pipes are made from “optimized” plastic
BMW claims there is no performance difference other than the increase in weight which adds about 30 lbs.
|
Nobody is arguing power stock vs. stock (N51 vs. N52). However if the N51 is essentially the same as the N52 high output just detuned to accomodate a different piston crown design then the potential for flashing/reflashing has to be slightly better in the N51 considering we already have the 3 stage manifold right out of the box. IMHO